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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Create a Two Dimensional Array

Posted by hemanta Subedi
.a{fill-rule:evenodd;}techdegree
hemanta Subedi
Full Stack JavaScript Techdegree Student 2,613 Points

Pleasure help me

I don't have idea

script.js 
var coordinates = [ [1,2], [2,3], [3,4], [9,10] ];
coordinates.push([12, 20]);
coordinates.push([1,2],[3,4],[5,6])
var coordinates = [ '[2,3] [3,1]  [5,10]' ];
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Objects</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

2 Answers

hemanta Subedi
.a{fill-rule:evenodd;}techdegree
hemanta Subedi
Full Stack JavaScript Techdegree Student 2,613 Points

Thanks a lot

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,722 Points
Jeff Muday
Jeff Muday
Treehouse Moderator 28,722 Points

It looks like you have studied some JavaScript syntax-- let's work with that. I will use the parts of your code which were working in isolation.

Let's solve EACH part of the challenge below-- I copied in-place your code ;-)

part 1 - declare an empty array named coordinates. A possible solution is below.

var coordinates = [];  // this is just a declaration of an empty array.

part 2 - add on an array of 2 elements to coordinates. A possible solution is below. Notice the second line from your code, is used with an empty array declared on the first line called coordinates.

var coordinates = []; // this is just a declaration of an empty array.
coordinates.push([12,20]); // this adds a new item to the coordinates array.

part 3 - make the array hold 4 sets of coordinates. You can just use your first line as a "declarative approach." This is a possible solution that will work. I copied the first line of your solution in to show you that it works on its own!

var coordinates = [ [1,2], [2,3], [3,4], [9,10] ]; // this works as a declarative approach to solving the challenge.

part 3 - Alternative "builder" approach

var coordinates = []; // this is just a declaration of an empty array.
coordinates.push([1, 2]); // push on a first element
coordinates.push([2, 3]); // push on a second
coordinates.push([3, 4]); // push on a third
coordinates.push([9, 10]); // push on a fourth